Re: [PATCH] Really *do* nothing in while loop

[J.A. Magallon]

On 05.08, Michael Tokarev wrote:
> Thomas Glanzmann wrote:
> > [PATCH] Really *do* nothing in while loop
> > 
> > Signed-Off-by: Thomas Glanzmann <sithglan@xxxxxxxxxxxxxxxxxxxx>
> > 
> > --- a/sha1_file.c
> > +++ b/sha1_file.c
> > @@ -335,7 +335,7 @@
> >  	stream.next_in = hdr;
> >  	stream.avail_in = hdrlen;
> >  	while (deflate(&stream, 0) == Z_OK)
> > -		/* nothing */
> > +		/* nothing */;
> >  
> >  	/* Then the data itself.. */
> >  	stream.next_in = buf;
> 
> Well, the lack of semicolon is wrong really (and funny).
> 
> But is the whole while loop needed at all?  deflate()
> consumes as much input as it can, producing as much output
> as it can.  So without the loop, and without updating the
> buffer pointers ({next,avail}_{in,out}) it will do just
> fine without the loop, and will return something != Z_OK
> on next iteration.  If this is to mean to flush output,
> it should be deflate(&stream, Z_FLUSH) or something.
> 

This changes the code in the corner case when deflate(...) IS NOT Z_OK
in the first iteration.
Old code: next_in is not assigned if deflate(&stream, 0) != Z_OK
New code: next_is is _always_ assigned

Other point is if old code was wrong...hidden bug ?

--
J.A. Magallon <jamagallon()able!es>     \               Software is like sex:
werewolf!able!es                         \         It's better when it's free
Mandriva Linux release 2006.0 (Cooker) for i586
Linux 2.6.11-jam16 (gcc 4.0.0 (4.0.0-3mdk for Mandriva Linux release 2006.0))


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